Mer-Type Creatures
Sirens - These creatures are forever being confused with mermaids. Sirens have the upper body of a young woman and the lower body of a bird (Similar to Harpies, but the Harpies are crones and vile creatures). These creatures were known to sing sailors to their deaths as they crashed upon the rocky reefs hidden beneith the waves as they followed the enchanting music.
Water Nymphs - Human form creatures that were well known for their singing and playing of a musical instsument. Thse creatures were also known, like the mermaids, to hold the most beautiful of form.
Nereids - Were the daughters of Nereus and the Oceanides, who were associated with Ocean and the Naiads who lived in the fresh waters of the ancient world, while being water creatures were depicted as humans and not merpeople.